CVE-2026-56742: Cilium

High severity, CVSS 8.9. EPSS: 0.2% chance of exploitation in the next 30 days.

Cilium is a networking, observability, and security solution. Prior to 1.17.17, 1.18.11, and 1.19.5, Cilium clusters using Gateway API allow users with permissions to create or update namespaced HTTPRoutes to mirror HTTP traffic to any Service in any namespace, bypassing the ReferenceGrant authorization mechanism. Gateway API functionality is disabled by default. This issue is fixed in versions 1.17.17, 1.18.11, and 1.19.5.

Affected products

• Cilium Cilium: before 1.17.17 (fixed in 1.17.17); from 1.18.0, before 1.18.11 (fixed in 1.18.11); from 1.19.0, before 1.19.5 (fixed in 1.19.5)

Published 2026-07-15. Last modified 2026-07-17.